1. Field of the Invention
This invention relates to magnetic recording and/or reproducing apparatus, and more particularly to magnetic recording and/or reproducing apparatus using disc-shaped magnetic record bearing media having a magnetizable members mounted at their centers, and to the magnetic recording discs themselves.
2. Description of the Prior Art
In an apparatus for recording or reproducing video signals and data signals on a storage such as a disc-shaped flexible magnetic sheet, the latter must be steadily and precisely set on the spindle for rotation. Previously, the center hub of the magnetic disc has been provided with a magnetizable plate, such as an iron ring, and the spindle has been provided with a permanent magnet to attract the magnetizable plate. The aim is to provide a steady setting of the magnetic disc by a magnetic chuck.
If the permanent magnet on the spindle has its direction of magnetization coincident with the axis of the spindle, the magnetic flux propagates through the magnetizable plate in the center hub of the magnetic sheet to the recording and/or reproducing head. This creates several potential drawbacks or disadvantages. Specifically, the head can be magnetized badly, and this can deteriorate the quality of the recording or reproducing signal because the leaking magnetic flux distorts the operation of the record bearing medium.